// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE

(function(mod) {
  if (typeof exports == "object" && typeof module == "object") // CommonJS
	mod(require("../../lib/codemirror"));
  else if (typeof define == "function" && define.amd) // AMD
	define(["../../lib/codemirror"], mod);
  else // Plain browser env
	mod(CodeMirror);
})(function(CodeMirror) {
  "use strict";

  var HINT_ELEMENT_CLASS        = "CodeMirror-hint";
  var ACTIVE_HINT_ELEMENT_CLASS = "CodeMirror-hint-active";

  // This is the old interface, kept around for now to stay
  // backwards-compatible.
  CodeMirror.showHint = function(cm, getHints, options) {
	if (!getHints) return cm.showHint(options);
	if (options && options.async) getHints.async = true;
	var newOpts = {hint: getHints};
	if (options) for (var prop in options) newOpts[prop] = options[prop];
	return cm.showHint(newOpts);
  };

  var asyncRunID = 0;
  function retrieveHints(getter, cm, options, then) {
	if (getter.async) {
	  var id = ++asyncRunID;
	  getter(cm, function(hints) {
		if (asyncRunID == id) then(hints);
	  }, options);
	} else {
	  then(getter(cm, options));
	}
  }

  CodeMirror.defineExtension("showHint", function(options) {
	// We want a single cursor position.
	if (this.listSelections().length > 1 || this.somethingSelected()) return;

	if (this.state.completionActive) this.state.completionActive.close();
	var completion = this.state.completionActive = new Completion(this, options);
	var getHints = completion.options.hint;
	if (!getHints) return;

	CodeMirror.signal(this, "startCompletion", this);
	return retrieveHints(getHints, this, completion.options, function(hints) { completion.showHints(hints); });
  });

  function Completion(cm, options) {
	this.cm = cm;
	this.options = this.buildOptions(options);
	this.widget = this.onClose = null;
  }

  Completion.prototype = {
	close: function() {
	  if (!this.active()) return;
	  this.cm.state.completionActive = null;

	  if (this.widget) this.widget.close();
	  if (this.onClose) this.onClose();
	  CodeMirror.signal(this.cm, "endCompletion", this.cm);
	},

	active: function() {
	  return this.cm.state.completionActive == this;
	},

	pick: function(data, i) {
	  var completion = data.list[i];
	  if (completion.hint) completion.hint(this.cm, data, completion);
	  else this.cm.replaceRange(getText(completion), completion.from || data.from,
								completion.to || data.to, "complete");
	  CodeMirror.signal(data, "pick", completion);
	  this.close();
	},

	showHints: function(data) {
	  if (!data || !data.list.length || !this.active()) return this.close();

	  if (this.options.completeSingle && data.list.length == 1)
		this.pick(data, 0);
	  else
		this.showWidget(data);
	},

	showWidget: function(data) {
	  this.widget = new Widget(this, data);
	  CodeMirror.signal(data, "shown");

	  var debounce = 0, completion = this, finished;
	  var closeOn = this.options.closeCharacters;
	  var startPos = this.cm.getCursor(), startLen = this.cm.getLine(startPos.line).length;

	  var requestAnimationFrame = window.requestAnimationFrame || function(fn) {
		return setTimeout(fn, 1000/60);
	  };
	  var cancelAnimationFrame = window.cancelAnimationFrame || clearTimeout;

	  function done() {
		if (finished) return;
		finished = true;
		completion.close();
		completion.cm.off("cursorActivity", activity);
		if (data) CodeMirror.signal(data, "close");
	  }

	  function update() {
		if (finished) return;
		CodeMirror.signal(data, "update");
		retrieveHints(completion.options.hint, completion.cm, completion.options, finishUpdate);
	  }
	  function finishUpdate(data_) {
		data = data_;
		if (finished) return;
		if (!data || !data.list.length) return done();
		if (completion.widget) completion.widget.close();
		completion.widget = new Widget(completion, data);
	  }

	  function clearDebounce() {
		if (debounce) {
		  cancelAnimationFrame(debounce);
		  debounce = 0;
		}
	  }

	  function activity() {
		clearDebounce();
		var pos = completion.cm.getCursor(), line = completion.cm.getLine(pos.line);
		if (pos.line != startPos.line || line.length - pos.ch != startLen - startPos.ch ||
			pos.ch < startPos.ch || completion.cm.somethingSelected() ||
			(pos.ch && closeOn.test(line.charAt(pos.ch - 1)))) {
		  completion.close();
		} else {
		  debounce = requestAnimationFrame(update);
		  if (completion.widget) completion.widget.close();
		}
	  }
	  this.cm.on("cursorActivity", activity);
	  this.onClose = done;
	},

	buildOptions: function(options) {
	  var editor = this.cm.options.hintOptions;
	  var out = {};
	  for (var prop in defaultOptions) out[prop] = defaultOptions[prop];
	  if (editor) for (var prop in editor)
		if (editor[prop] !== undefined) out[prop] = editor[prop];
	  if (options) for (var prop in options)
		if (options[prop] !== undefined) out[prop] = options[prop];
	  return out;
	}
  };

  function getText(completion) {
	if (typeof completion == "string") return completion;
	else return completion.text;
  }

  function buildKeyMap(completion, handle) {
	var baseMap = {
	  Up: function() {handle.moveFocus(-1);},
	  Down: function() {handle.moveFocus(1);},
	  PageUp: function() {handle.moveFocus(-handle.menuSize() + 1, true);},
	  PageDown: function() {handle.moveFocus(handle.menuSize() - 1, true);},
	  Home: function() {handle.setFocus(0);},
	  End: function() {handle.setFocus(handle.length - 1);},
	  Enter: handle.pick,
	  Tab: handle.pick,
	  Esc: handle.close
	};
	var custom = completion.options.customKeys;
	var ourMap = custom ? {} : baseMap;
	function addBinding(key, val) {
	  var bound;
	  if (typeof val != "string")
		bound = function(cm) { return val(cm, handle); };
	  // This mechanism is deprecated
	  else if (baseMap.hasOwnProperty(val))
		bound = baseMap[val];
	  else
		bound = val;
	  ourMap[key] = bound;
	}
	if (custom)
	  for (var key in custom) if (custom.hasOwnProperty(key))
		addBinding(key, custom[key]);
	var extra = completion.options.extraKeys;
	if (extra)
	  for (var key in extra) if (extra.hasOwnProperty(key))
		addBinding(key, extra[key]);
	return ourMap;
  }

  function getHintElement(hintsElement, el) {
	while (el && el != hintsElement) {
	  if (el.nodeName.toUpperCase() === "LI" && el.parentNode == hintsElement) return el;
	  el = el.parentNode;
	}
  }

  function Widget(completion, data) {
	this.completion = completion;
	this.data = data;
	var widget = this, cm = completion.cm;

	var hints = this.hints = document.createElement("ul");
	hints.className = "CodeMirror-hints";
	this.selectedHint = data.selectedHint || 0;

	var completions = data.list;
	for (var i = 0; i < completions.length; ++i) {
	  var elt = hints.appendChild(document.createElement("li")), cur = completions[i];
	  var className = HINT_ELEMENT_CLASS + (i != this.selectedHint ? "" : " " + ACTIVE_HINT_ELEMENT_CLASS);
	  if (cur.className != null) className = cur.className + " " + className;
	  elt.className = className;
	  if (cur.render) cur.render(elt, data, cur);
	  else elt.appendChild(document.createTextNode(cur.displayText || getText(cur)));
	  elt.hintId = i;
	}

	var pos = cm.cursorCoords(completion.options.alignWithWord ? data.from : null);
	var left = pos.left, top = pos.bottom, below = true;
	hints.style.left = left + "px";
	hints.style.top = top + "px";
	// If we're at the edge of the screen, then we want the menu to appear on the left of the cursor.
	var winW = window.innerWidth || Math.max(document.body.offsetWidth, document.documentElement.offsetWidth);
	var winH = window.innerHeight || Math.max(document.body.offsetHeight, document.documentElement.offsetHeight);
	(completion.options.container || document.body).appendChild(hints);
	var box = hints.getBoundingClientRect(), overlapY = box.bottom - winH;
	if (overlapY > 0) {
	  var height = box.bottom - box.top, curTop = pos.top - (pos.bottom - box.top);
	  if (curTop - height > 0) { // Fits above cursor
		hints.style.top = (top = pos.top - height) + "px";
		below = false;
	  } else if (height > winH) {
		hints.style.height = (winH - 5) + "px";
		hints.style.top = (top = pos.bottom - box.top) + "px";
		var cursor = cm.getCursor();
		if (data.from.ch != cursor.ch) {
		  pos = cm.cursorCoords(cursor);
		  hints.style.left = (left = pos.left) + "px";
		  box = hints.getBoundingClientRect();
		}
	  }
	}
	var overlapX = box.right - winW;
	if (overlapX > 0) {
	  if (box.right - box.left > winW) {
		hints.style.width = (winW - 5) + "px";
		overlapX -= (box.right - box.left) - winW;
	  }
	  hints.style.left = (left = pos.left - overlapX) + "px";
	}

	cm.addKeyMap(this.keyMap = buildKeyMap(completion, {
	  moveFocus: function(n, avoidWrap) { widget.changeActive(widget.selectedHint + n, avoidWrap); },
	  setFocus: function(n) { widget.changeActive(n); },
	  menuSize: function() { return widget.screenAmount(); },
	  length: completions.length,
	  close: function() { completion.close(); },
	  pick: function() { widget.pick(); },
	  data: data
	}));

	if (completion.options.closeOnUnfocus) {
	  var closingOnBlur;
	  cm.on("blur", this.onBlur = function() { closingOnBlur = setTimeout(function() { completion.close(); }, 100); });
	  cm.on("focus", this.onFocus = function() { clearTimeout(closingOnBlur); });
	}

	var startScroll = cm.getScrollInfo();
	cm.on("scroll", this.onScroll = function() {
	  var curScroll = cm.getScrollInfo(), editor = cm.getWrapperElement().getBoundingClientRect();
	  var newTop = top + startScroll.top - curScroll.top;
	  var point = newTop - (window.pageYOffset || (document.documentElement || document.body).scrollTop);
	  if (!below) point += hints.offsetHeight;
	  if (point <= editor.top || point >= editor.bottom) return completion.close();
	  hints.style.top = newTop + "px";
	  hints.style.left = (left + startScroll.left - curScroll.left) + "px";
	});

	CodeMirror.on(hints, "dblclick", function(e) {
	  var t = getHintElement(hints, e.target || e.srcElement);
	  if (t && t.hintId != null) {widget.changeActive(t.hintId); widget.pick();}
	});

	CodeMirror.on(hints, "click", function(e) {
	  var t = getHintElement(hints, e.target || e.srcElement);
	  if (t && t.hintId != null) {
		widget.changeActive(t.hintId);
		if (completion.options.completeOnSingleClick) widget.pick();
	  }
	});

	CodeMirror.on(hints, "mousedown", function() {
	  setTimeout(function(){cm.focus();}, 20);
	});

	CodeMirror.signal(data, "select", completions[0], hints.firstChild);
	return true;
  }

  Widget.prototype = {
	close: function() {
	  if (this.completion.widget != this) return;
	  this.completion.widget = null;
	  this.hints.parentNode.removeChild(this.hints);
	  this.completion.cm.removeKeyMap(this.keyMap);

	  var cm = this.completion.cm;
	  if (this.completion.options.closeOnUnfocus) {
		cm.off("blur", this.onBlur);
		cm.off("focus", this.onFocus);
	  }
	  cm.off("scroll", this.onScroll);
	},

	pick: function() {
	  this.completion.pick(this.data, this.selectedHint);
	},

	changeActive: function(i, avoidWrap) {
	  if (i >= this.data.list.length)
		i = avoidWrap ? this.data.list.length - 1 : 0;
	  else if (i < 0)
		i = avoidWrap ? 0  : this.data.list.length - 1;
	  if (this.selectedHint == i) return;
	  var node = this.hints.childNodes[this.selectedHint];
	  node.className = node.className.replace(" " + ACTIVE_HINT_ELEMENT_CLASS, "");
	  node = this.hints.childNodes[this.selectedHint = i];
	  node.className += " " + ACTIVE_HINT_ELEMENT_CLASS;
	  if (node.offsetTop < this.hints.scrollTop)
		this.hints.scrollTop = node.offsetTop - 3;
	  else if (node.offsetTop + node.offsetHeight > this.hints.scrollTop + this.hints.clientHeight)
		this.hints.scrollTop = node.offsetTop + node.offsetHeight - this.hints.clientHeight + 3;
	  CodeMirror.signal(this.data, "select", this.data.list[this.selectedHint], node);
	},

	screenAmount: function() {
	  return Math.floor(this.hints.clientHeight / this.hints.firstChild.offsetHeight) || 1;
	}
  };

  CodeMirror.registerHelper("hint", "auto", function(cm, options) {
	var helpers = cm.getHelpers(cm.getCursor(), "hint"), words;
	if (helpers.length) {
	  for (var i = 0; i < helpers.length; i++) {
		var cur = helpers[i](cm, options);
		if (cur && cur.list.length) return cur;
	  }
	} else if (words = cm.getHelper(cm.getCursor(), "hintWords")) {
	  if (words) return CodeMirror.hint.fromList(cm, {words: words});
	} else if (CodeMirror.hint.anyword) {
	  return CodeMirror.hint.anyword(cm, options);
	}
  });

  CodeMirror.registerHelper("hint", "fromList", function(cm, options) {
	var cur = cm.getCursor(), token = cm.getTokenAt(cur);
	var found = [];
	for (var i = 0; i < options.words.length; i++) {
	  var word = options.words[i];
	  if (word.slice(0, token.string.length) == token.string)
		found.push(word);
	}

	if (found.length) return {
	  list: found,
	  from: CodeMirror.Pos(cur.line, token.start),
			to: CodeMirror.Pos(cur.line, token.end)
	};
  });

  CodeMirror.commands.autocomplete = CodeMirror.showHint;

  var defaultOptions = {
	hint: CodeMirror.hint.auto,
	completeSingle: true,
	alignWithWord: true,
	closeCharacters: /[\s()\[\]{};:>,]/,
	closeOnUnfocus: true,
	completeOnSingleClick: false,
	container: null,
	customKeys: null,
	extraKeys: null
  };

  CodeMirror.defineOption("hintOptions", null);
});
